Black powder and jacketed bullets???

[jhalcott]

 Since I have a couple hundred Hornady 300 grain jacketed bullets and a couple 45-70's what's the problem with using the bullets with black powder? What should I watch out for when doing this.? I don't use the 45-70 for hunting much any more,but we do have a shoot at the club annually that requires at least a 40 caliber rifle. Both black and smokeless classes are shot. The guns are a bolt action rifle and a couple Contender barrels. I DO cast some 405 and 300 grain bullets for it, just thinking about using the jacketed slugs for a change.

[John Traveler]

There is nothing wrong at all with combining BP with jacketed bullets.  It's just that competition BPCR prohibits the use of jacketed or gas checked bullets.

You do need to THOROUGHLY clean the barrel of all bullet residue before switching to the other.  Changing bullet materials without doing so can make for particularly difficult to clean bore deposits and can affect accuracy too.